@CHARSET "ISO-8859-1";

.caixa {        
     position: relative;
     left: 50%;
     top: 50px;
     margin-left: -150px;
     padding: 15px;
     width: 300px;     
}

input[type="text"] {
     position: relative;
     left: 10%;
}

input[type="submit"] {
     position: relative;
     left: 100%;
     margin-left: -100px;
     width: 100px; 
}
